Add RemBERT ONNX config

[hchings]

What does this PR do?

Add RemBERT ONNX config (part of #16308)

The max absolute difference between reference model and ONNX exported model is around 2e-05 in testings. I learned from other PRs that this discrepancy is within an acceptable range so I loosen the default atol.

Slow tests are passed (RUN_SLOW=1 pytest tests/onnx/test_onnx_v2.py -k "rembert").

I'm new to contributing to Transformers. If anyone can help me understand what is lacking, it would be appreciated!

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• Did you write any new necessary tests?

Who can review?

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag
members/contributors who may be interested in your PR.

@lewtun & @chainyo for ONNX and @Iwontbecreative for RemBERT.

[HuggingFaceDocBuilderDev]

The documentation is not available anymore as the PR was closed or merged.

[chainyo]

Hi @hchings, the PR looks excellent! Did you try to run tests locally?

RUN_SLOW=1 pytest tests/onnx/test_onnx_v2.py -k "rembert"

Could you also remove the Fixes #... before the link to the ONNX issue to avoid an auto-close from GitHub? Thanks a lot for your contribution!

[hchings]

Hi @hchings, the PR looks excellent! Did you try to run tests locally?

RUN_SLOW=1 pytest tests/onnx/test_onnx_v2.py -k "rembert"

Could you also remove the Fixes #... before the link to the ONNX issue to avoid an auto-close from GitHub? Thanks a lot for your contribution!

Yes, all slow tests passed for PyTorch locally. Should we add TensorFlow tests as well? My understanding is TF tests are needed only when TF has parity with PyTorch implementations. But correct me if I'm wrong.

[chainyo]

Ok looks good. Let's see wait on @lewtun.

[sgugger]

Thanks for your contribution!